Cutting blade assemblies are used in a wide variety of applications to generally reduce the particle size of the medium being processed. Grinder pumps include a motor that rotates an impeller and an associated cutting blade assembly. Fluid and debris suspended within the fluid are drawn into the grinder pump where the cutting blade assembly attempts to reduce the particle size of the suspended debris before the impeller pumps the resulting slurry to a downstream location.
One issue common to most cutting blade assemblies, and especially those incorporated in a grinder pump or other fluid pumping applications, is the efficient processing and jam-free operation of the cutting blade assembly given the wide variety of debris encountered. For instance, with grinder pumps, debris including rags, mop heads, beverage containers, diapers, coins, and other objects can clog and jam the cutting blade assembly or place an increased load on the motor driving the cutting blade assembly. The various types of debris present many challenges because stringy debris (e.g., a mop head) can tend to wrap around the cutting blade assembly, resilient debris (e.g., plastic and rubber objects) can tend to wedge between moving parts of the cutting blade assembly, and hard debris (e.g., metallic objects) can wear or damage the cutting features of the cutting blade assembly.
To address these various problems associated with processing a variety of suspended debris, the drive motor torque can be increased, the cutting blade assembly strengthened, and the allowable particle size increased. However, none of these approaches presents an efficient, cohesive technique to address the persistent issues faced by cutting blade assemblies, and especially those cutting blade assemblies used in grinder pump applications.